Jade trees, even in pots, have a look of long-livedness to them, a sense of patience that promises tolerance for even inexperienced indoor gardeners. Looks do not deceive. The plants aren't fussy. Treat them with courtesy and jade trees will live for a long time, reaching about 5 feet if potted, perhaps even blooming eventually. Part of the courtesy owed jades is not to over-water, a common mistake of those growing jade plants.
Make sure the soil drains well or risk causing the jade to develop root rot.
Re-pot the jade with appropriate soil if needed, preferably doing so when dormancy is over. Don't water afterward; let the soil dry out before you next water the plant.
Place the jade in full sun or a southern window. Don't let the jade plant actually touch the window. Jades need at least four hours of sun daily.
Water regularly--about once a week during spring and summer, once a month in winter. Let soil dry between waterings.
Inspect for pests when you water. Mealybugs are a common jade pest. They look like small bits of cotton.
Rub off pests with cotton swabs dipped in alcohol.
Fertilize the plant about once a quarter, following the directions on the fertilizer. Don't fertilize while the plant is dormant.
Re-pot to a larger pot if years of growth make the plant in danger of tipping over. Do this during the growing season. After re-potting, let the soil dry out before watering again.
Prune new growth when it's young if it will end up producing a branch in a direction you don't want. You don't want the plant to end up unbalanced. Cut back to the lateral branch or main trunk.